The present invention relates to a metal plating and purification process and more particularly to a photoelectrochemical metal plating and purification process capable of converting light energy directly to chemical energy and utilizing this energy to electro-deposit metals at a suitable electrode.
It has been discovered that water can be photodissociated into hydrogen and oxygen at very low electrical potentials by using titanium dioxide or other semiconductor electrodes and a light source rich in energy in the ultraviolet region of the electromagnetic spectrum. This discovery has opened a new area of research into the conversion of solar energy into stored chemical energy. For example, hydrogen generated by the photodissociation of water can be stored for later use either as the gas per se, or as a metal hydride.
Other uses for solar energy utilizing these semiconducting electrodes involve the direct conversion of light energy into chemical energy for purposes of driving other chemical reactions.